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DECONSTRUCTING LIVE IP
Overview and Analysis of IP Protocols for Television Production
A Broadcast Industry White Paper Sponsored by:
www.alphavideo.com
1
Table Of Contents
INTRODUCTION
01 The great promise of IP is to create a truly open and interoperable environment for the
smooth plug and play of best of breed technologies. IP is a bit like SDI, in fact, but with
Page-03
greater potential for economic and creative benefit.
A NOTE ON MAPPING SDI
02 SDI has served for years as the common language of uncompressed video in broadcast
facilities for years, enabling any piece of equipment from any manufacturer to connect
Page-04
with any other equipment that also supports this standard.
FOUR APPROACHES TO LIVE IP
03 A comparison on the four approaches to live IP based on video, audio, data, synchronization,
and real world applications.
Page-05
COMPRESSION
04 A key point of differentiation between the protocols is compression. Page-08
CAN PROTOCOLS BE BRIDGED?
05 There are far more similarities than differences between the approaches. There are
distinguishing differences, notably around how to split the media essence and whether
Page-09
and what form compression should take.
JUST THE FACTS
06 This white paper does not make a claim for any of the approaches but has laid out the
facts as they stand.
Page-12
2
01. Introduction
T
he broadcast and media industry’s transition from Serial Digital Interface (SDI) to Internet Protocol (IP) as
the primary means of moving signals between and through facilities is well and truly upon us. With the
transition comes the promise of increased agility and system scalability that can help broadcasters develop
new business models and to remain competitive. While there’s no longer a question as to whether or not a
transition is necessary, opinions are quite varied regarding the pace and level of priority a broadcaster should be
placing on the transition.
The Promise of IP
The great promise of IP is to create a truly open and by any international standards body – reliant on
interoperable environment for the smooth plug and drafts or Registered Disclosure Documents (RDD) -
play of best of breed technologies. IP is a bit like SDI, and the degree of openness is up for interpretation.
in fact, but with greater potential for economic and
creative benefit. Each offers a solution to the same problem: IP in
the live production environment. This is the biggest
One impediment to this transition is that multiple, challenge for IP due to the nature of the application.
competing approaches to the transition are being Low latency in conjunction with discrete and reliable
introduced, complicating an already daunting switching is required.
decision for broadcasters, live event producers,
news organizations and corporate AV users. These All the approaches recognize that IP affords the
approaches are promoted under the brands: AIMS, opportunity to move from the constraints of SDI to
ASPEN, NewTek NDI and Sony NMI. allow for independent video, audio, and metadata
streams. The differences between the groups is,
Each of these brands can count multiple backers, all broadly, how to deliver this.
claim to be standards-based and all claim to be an
open system. But no scheme has been fully ratified
3
02. A Note on Mapping SDI to IP
SDI has served for years as the common language of uncompressed video in broadcast facilities for years,
enabling any piece of equipment from any manufacturer to connect with any other equipment that also
supports this standard.
Taking this as a baseline, standards body SMPTE ratified a standard for mapping HD-SDI signals over an IP
network. This is called SMPTE 2022-6 and its key characteristics are that it transports uncompressed media
and is intended to mirror the video switching functionality of traditional SDI-based systems.
Limitations of SMPTE 2022-6
The chief limitation of SMPTE 2022-6 is that by mapping the whole SDI payload including video, audio and
metadata as a package, it cannot deal with video, audio and metadata independently. For some, this nullifies
one of the most beneficial aspects of moving to IP which is to add greater flexibility and control into the
handling of media. An example might be efficiently connecting different audio tracks with a video.
THE ISSUE WITH AUDIO
With SMPTE 2022-6, the entire video stream must first be de-packetized and then the audio signal de-embedded
from the SDI stream. Once processing is completed, the audio must be re-embedded into SDI before the SDI
signal can once again be packetized.
This is why three of the approaches have developed or promote technologies which pass individual streams
of audio, video and metadata through a network, to be re-composed into different combinations as needed
for production purposes. The fourth approach, NewTek NDI, utilizes a distinct approach compared to the
competitive protocols.
4
03. Four Approaches to Live IP Production
AIMS
The marketing organization Alliance for IP Media Solutions was launched in December 2015. It is not a standards
body nor does it develop any technology, but its members are lobbying for a set of standards developed by
bodies like the Video Services Forum (VSF) and the Advanced Media Workflow Association (AMWA), and with
the support of organizations like the European Broadcasting Union. Its founding members are Nevion, Grass
Valley, Imagine Communications, Lawo and Snell Advanced Media.
AIMS has a three-phased approach to introducing IP into existing facilities
NUTS & BOLTS building on SMPTE 2022-6 and extending this with tools to split the media
essence.
AIMS’ starting point is SMPTE 2022-6 but it recommends combining this with
VIDEO a protocol called TR-04. This was devised by the VSF and links SMPTE 2022-6
for video with embedded audio and AES67 for separate IP addressable audio
streams. AIMS says that this makes TR-04 suitable for systems that require
both the compatibility benefits of SMPTE 2022-6 and the flexibility of discrete
audio.
AIMS goes further in that it recommends that video and metadata as well
as audio be individually packetized into separate IP streams. This was also
devised at the VSF and is called TR-03. The idea is that TR-03 would replace the
SMPTE 2022-6 portion of TR-04 with an improved method for distributing video
data. The work on TR-03 and TR-04 is being documented as SMPTE 2110. It is
not yet a standard.
TR-03 uses AES67 for audio, a standard widely accepted by audio equipment
AUDIO & DATA suppliers for high performance audio over IP.
For timing over IP, TR-03 specifies SMPTE ST 2059-2 (which builds on the IEEE
SYNCHRONIZATION 1588 Precision Time Protocol / PTP).
The highest profile tests conducted using AIMS’ recommended protocols was
APPLICATIONS made at Belgium broadcaster VRT. A number of AIMS vendors collaborated to
build an all IP live studio which was used successfully to produce and air a live
outside broadcast of a concert. This was based on SMPTE 2022-6, AES67 and
PTP but did not trial TR-03 or any form of compression.
AIMS projects that systems using the SMPTE/VSF-based interoperability
roadmap will be “fully realizable in 2016 with system implementations from
multiple companies.”
AIMS has also agreed to support the AMWA NMOS (Networked Media Open
Specifications) initiative for discovery and registration of services over IP. This
means that two manufacturers connecting equipment to a network will be
able to ‘discover’ each other and use each other’s services and outputs/inputs.
5
ASPEN
Developed by Evertz, Adaptive Sample Picture Encapsulation (ASPEN) was launched in April 2015.
Like AIMS, ASPEN is focused on splitting the audio, video and metadata
NUTS & BOLTS streams. Unlike AIMS, it does so using existing and draft MPEG protocols.
ASPEN takes uncompressed SD, HD, 3G and Ultra HD video signals and
VIDEO packetizes them into an MPEG-2 Transport Stream (TS). This encapsulation
method is documented in SMPTE draft RDD-37.
For transporting audio and ancillary data ASPEN makes use of existing
AUDIO & DATA standards. Embedded or discrete AES audio is processed according to SMPTE
ST 302. Metadata is handled according to SMPTE ST 2038.
ASPEN uses the existing timing mechanisms of the MPEG-2 Transport Stream
SYNCHRONIZATION to align audio, video and metadata. ASPEN is compatible with SMPTE ST 2059
PTP-based synchronization.
ASPEN is already implemented by existing Evertz customers including Dome
APPLICATIONS Productions, Game Creek, NEP Group, NBC Sports, Time Warner Cable Sports
and Discovery Communications
NDI
Eschewing the approach of what it would call ‘traditional broadcast’ equipment vendors, NewTek launched the
Network Device Interface in September 2015.
NDI routes video over IP on a 1Gbit network connection, with bandwidth
NUTS & BOLTS consumption generally ranging from 50-100Mbps per video stream. NewTek is
aiming NDI at lower-budget broadcast, corporate communications, houses of
worship, and niche sports streamers.
A key trait of NDI is that it permits two-way signal transmission over IP. This
VIDEO means a NDI-enabled switcher can simultaneously send multiple input and
output signals to the network for transport to multiple NDI destinations, and
receive the input and output signals of every other NDI-enabled device over the
network for use as sources. Of course, this presupposes that each part of the
chain is NDI-enabled.
NDI is format-agnostic. It accepts and supports interoperability between audio
AUDIO & DATA sources including AES67 and Dante, in addition to audio sources attached to
NDI-enabled systems and devices which are subsequently ‘translated’ to NDI
and made available for use by other NDI-enabled systems and devices on the
network.
This is a common question when comparing NDI to other formats. Fundamentally,
SYNCHRONIZATION NDI is a different technology and for this reason, NewTek sees NDI as being a
format that will allow for expansion of video production at all levels, including
those that use protocols such as ASPEN. Put another way, NDI does not require
synchronization to work.
NewTek offers NDI as a free SDK to developers and video producers wanting to
APPLICATIONS implement it into products and workflows. It claims that it supports more than
100,000 devices in use today.
6 www.corporatedomain.com
SONY NMI
Sony was first out of the block with a live production IP protocol launching the Networked Media Interface in
September 2014.
It is based on SMPTE ST 2022-6 and therefore for packaged transfer of
NUTS & BOLTS uncompressed HD-SDI over an IP network. For media requiring higher bandwidth,
such as 4K video, Sony has developed and promotes its own codec within NMI
(see below).
NMI supports SMPTE 2022-6 (where the essences are not discriminated) but
VIDEO it also employs its own means of mapping of SDI audio, video and metadata
information, calling this Sony Essence. Sony says this approach has the
advantage of keeping lip sync information coherent in contrast to TR-03 which –
Sony argues - splits essence into separate RTP Streams while optimizing the use
of available bandwidth. Both approaches have their pros and cons, says Sony.
In the future, Sony says it will support the SMPTE 2110 (currently TR-03) media
transport method.
The Live System Manager solution from Sony, which supports NMI, manages
AUDIO & DATA audio and video routing linked or independently. The audio is converted in
DANTE / AES 67 for audio processing by third party products which support Sony
NMI (Yamaha and Audinate, for example).
Sony uses SMPTE ST 2059-2.
SYNCHRONIZATION
Sony has developed a system on a chip called LSI which is equipped with
APPLICATIONS the encoding/decoding function of its codec plus network packetizing and
synchronization. The company is embedding LSI into a variety of its own
equipment as well as offering it to third party vendors to integrate into their
product.
For interoperability with legacy devices that only feature an SDI interface, Sony
has developed external conversion hardware that can support up to 4K signals.
Sony will point to the fact that it originally developed SDI as a proprietary
technology and that this became the de facto open industry standard.
7
04. Compression
What’s the Difference in Compression?
A key point of differentiation between the protocols is compression. While ASPEN and AIMS are nominally
uncompressed for routing Ultra HD over 10 GigE pipes, Sony (which has long had a marketing and product
development focus on 4K) includes use of its own codec within its protocol. By comparison, NewTek NDI offers
an uncompromisingly compressed approach but over ubiquitous 1 GigE pipes.
There is consensus that where production of 4K is needed today then a form of lightweight (mezzanine)
compression is required in order to reduce bandwidth consumption. This is even more the case as Ultra HD
attributes like High Dynamic Range, Wide Color Gamut and High Frame Rates are added to the equation, each
bumping up data rates.
Manufacturers are tending to adapt their core routing, switching and playout gear to include support for
multiple codec options, of which there are several. They include:
TICO. Developed by Belgium-firm IntoPix and based on the JPEG 2000 wavelet compression scheme. It
is a licensed codec supported by a coalition of companies branded The TICO Alliance. Members include
Blackmagic Design, EVS, Grass Valley, Ikegami, Imagine Communications, Matrox, Nevion, Panasonic,
Ross Video, Tektronix and Telestream.
VC-2. Based on wavelet compression. It was originated by the BBC as Dirac and standardized as SMPTE
2042. It is royalty-free.
Encoders based on Motion JPEG 2000 and MPEG-4 AVC which are other options for compressing data
over IP. Several manufacturers have developed these.
8How Do the IP Protocols Differ?
AIMS
A
IMS members tend to agree that compression is required for resolutions above HD and most will say
they are agnostic about the codec used. Some, however, have expressed a preference for one over
another. Snell Advanced Media, for example, states that an end-to-end IP system should be license free
and that it would vote for VC-2 over a scheme like TICO.
ASPEN
A
SPEN currently defines uncompressed video over MPEG-2 TS but has provision to add uncompressed
formats, including Sony LLVC and TICO, both of which Evertz says have benefits. In truth, compressed
video (MPEG-2, H.264, JPEG-2K) over IP has been done for years using MPEG-2 TS over IP with SMPTE
2022-2.
NEWTEK NDI
N
DI uses its own compression scheme to deliver what the company calls baseband quality (similar to
ProRes or DNXHD) of HD or 4K signals over 1GbE networks. “Most everyone will come to the same
conclusion,” NewTek President and CTO, Dr. Andrew Cross, told Streaming Media, “If you want to transport
uncompressed around then SDI is going to be better than IP. For instance, in TR-03, you need 10 microsecond
timing accuracy for each scan line of video. There’s just no way that a computer system without customized
hardware is ever going to be able to achieve that.”
SONY NMI
U
ses its own-designed Low Latency Video Codec (LLVC). The intention is to minimize latency to “within
several milliseconds”. Using LLVC, Sony say users can transmit up to four 1080i HD signals using a single
gigabit Ethernet cable, or two 4K signals using a single 10-GbE cable or a 4K 60p transmission over single
10 Gbps link. It is before SMPTE as RDD34.
www.corporatedomain.com 905. Can the Protocols be Bridged?
There are far more similarities than differences between the approaches. There are distinguishing
differences, notably around how to split the media essence and whether and what form compression should
take. The more fundamental differences are philosophical and center on how some protocols are viewed as
more proprietary and therefore less open, more costly to implement and less standards-based or potentially
inoperable, than others.
Sony and Evertz Join AIMS
Since April 2016 Evertz and Sony signaled that they commendable, but will not guarantee the level of
would support the rules of AIMS. That is, to promote compatibility that AIMS members are offering, AIMS
the use of agreed standards within bodies such as says.
SMPTE, VSF and EBU and specifically to promote the
use of the AIMS ‘roadmap’, that of SMPTE 2022-6 on Sony says that as part of the ASPEN community it
through the TR-03. provides products that support the ASPEN media
transport method. It is straightforward to integrate
For example, according to AIMS, a customer can buy a system camera chain with an Evertz audio/video
an Evertz Multiviewer that works in IP and a SAM infrastructure, for example, Sony says.
router and be sure that those two organizations will
work towards (or have already achieved) compatibility Sony NMI also encompasses the objectives of AIMS.
testing. The difference, according to Sony, is that where AIMS
focuses on the adoption of SMPTE 2022-6, TR-03 and
The same will apply in connection management. AES 67 and therefore mainly on the media transport
AIMS support of the NMOS devised by AMWA “does plane, Sony NMI is a wider approach. Sony says
not preclude additional mechanisms being used that NMI is more complete in the way that it covers the
may offer customers some advantages and enables seven planes of interoperability (media transport,
innovation across the market,” according to AIMS. timing, compression, flow control, flow switching,
device control and discovery, identity) as defined by
AIMS says it supports a base level of interoperability the Joint Task Force on Networked Media (EBU, VSF,
based on standards that are open and agreed upon SMPTE, AMWA). Sony does mention it will support
internationally. Other innovations and proposals are TR-03 when it is ratified as a standard.
10EVERTZ & NEWTEK
Evertz has also announced its support for the NewTek NDI
format based on its own Software Defined Video Networking
(SDVN) solutions. By adding NDI support, Evertz says this
benefits facilities transitioning to IP by taking advantage of a
10GbE core SDVN system to bridge a large number of NDI-
enabled devices, providing scalability and flexibility today and
into the future. Customers using Evertz SDVN will be able to
connect to the many products across the NewTek Developer
Network, it states.
With a workflow that’s already compatible with SDI equipment
NewTek says NDI will also support integration into SMPTE 2022
and other emerging standards.
NewTek on AIMS, ASPEN, Sony
NewTek restates its claim for NDI to be an open NewTek says it is fully supportive of all IP standards
protocol and notes that vendors, including its including the AIMS group. Since AIMS builds on SMPTE
competitors, have already started to include NDI in 2022 - which NDI can interface with via NewTek
their own products and more than 600 companies Connect Pro – a bridge is technically possible. “We
have downloaded the NDI SDK. Additionally, NewTek are already working with many of the streams (e.g.
has joined the ASPEN community for full integration TR-03) and will work to support any others as they
into that environment. become standardized,” NewTek advises.
For example, NewTek has a product to bridge At this time, NewTek says it is not aware of any
between worlds called NewTek Connect Pro. announcement from Sony that NMI will be available
Tighter integration between the two standards will to bridge to or communicate with it: “We would be
be forthcoming. NewTek has already worked with very happy to work with Sony on interoperability
vendors like Deltacast to bridge devices using SMPTE between our products and NDI and theirs,” it states.
2022.
1106. Just the Facts
This White Paper does not make a claim for any of the approaches but has laid out the
facts as they stand.
Once Size Does Not Fit All
None of these approaches on its own is intended leads others, this will come from popular use.”
to land customers in a silo workflow committed The transition to an all IT/IP system is different from
to one supplier and incapable of realizing the other technology developments in that it affects so
potential benefits of investment in IP. However, many aspects of the production/playout chain – it is
the combination of them does make the picture not just a box-for-box replacement within existing
confusing for customers and risks reducing buyer systems. The consequence is that workflows need to
confidence and fragmenting the industry. At worse it be re-designed, skill sets are different, new creative
threatens a format war. opportunities will develop and most important, the
technology deployment will be very different with
Understandably, the broadcast equipment vendor’s some commodity hardware, software solutions,
trade body International Association of Broadcast shared resources, cloud integration and virtual
Manufacturers (IABM), takes a diplomatic stance. machines.
“Industry standards remain important and should
continue to be one benchmark of stability,” it states. “All of this is going to take time to mature and evolve,”
“However, looking for a single standard is no longer stresses the IABM. “As there is no precedent for these
tenable for every aspect of the industry. The value of changes, we are facing a period of experimentation
standards is increasingly in the open documentation for some aspects. Fortunately, not everyone is facing
of important parameters, ensuring that more than one a refurbishment cycle at the same time.”
supplier can produce systems that will be compatible
or operate in a consistent way. If one standard
“ Looking for a single standard is no longer tenable for every aspect of the
industry. The value of standards is increasingly in the open documentation
of important parameters, ensuring that more than one supplier can produce
systems that will be compatible or operate in a consistent way. If one
standard leads others, this will come from popular use.” “
12 www.corporatedomain.comIP Protocol Basecamps
A sample of leading manufacturers and what IP protocols they currently support.*
Adobe •
AJA • • • •
Avid • •
Chyron • • •
Evertz • • • •
EVS • •
Grass Valley • •
Harmonic • •
Hitachi • •
Ikegami • •
Imagine • •
JVC •
LiveU •
NewTek • •
Ross Video •
Snell (S-A-M) •
Sony • • •
Utah Scientific •
VizRT • • • •
*Based on data that was available at the time of publication.
www.corporatedomain.com 13About the Sponsor
Alpha Video & Audio, Inc.
Alpha Video is a leading national software developer and professional systems integrator. They design, integrate,
and support audio, video, digital signage and broadcast systems that empower their clients to communicate
their vision.
QUESTIONS?
If you have questions about the content of this white paper, please contact Bryan Nelson, Alpha Video’s
Broadcast Account Executive.
Email: bryan.nelson@alphavideo.com
Phone: 952-841-3304 (o) or 612-819-7213 (m)
Twitter: @bryanalphavideo
EMAIL:
HEADQUARTERS PHONE: Info@alphavideo.com
7690 Golden Triangle Drive 800-388-0008
Eden Prairie, MN 55344 952-896-9898 WEB:
www.alphavideo.com
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